zorder -n 2 0 0 
zorder -n 3 0 1 
horder -n 2 0 0 
izorder -n 5 0    
izorder -n 2 15 
horder -n 2 0 0 
horder -n 1 0 1 
horder -n 2 0 1
ihorder -n 2 0 
ihorder -n 1 1 
ihorder -n 2 3 
zorder -n 3 10 10
zorder -n 3 10 11
horder -n 7 100 101
horder -n 8 100 101
ihorder -n 8 3000